From: Mike <michaelst@...>
Date: 2007-03-12T18:05:18+09:00
Subject: Re: #define alternative for Ruby

On Mar 12, 7:16 pm, Sebastian Hungerecker <sep...@googlemail.com>
wrote:
> ara.t.how...@noaa.gov wrote:
> > On Mon, 12 Mar 2007, Mike wrote:
> > > I was talking more about macros rather then constants.  But I agree that
> > > constant are convenient way to substitute "#define myconst 15". But can
> > > you substitute "#define myfunc(x) (sin(x)*cos(x)*exp(x))"?  You should
> > > know that "x" could be as much other functions as a constant/variable.
>
> > perhaps i'm being dense, but i fail to see how the above example is none
> > other than a simple function in ruby:
>
> Imagine you would call the function with rand() as parameter. With #define
> rand would be called three times, with def it would be called once and its
> value would be used three times.
>
> --
> Ist so, weil ist so
> Bleibt so, weil war so

Just try to implement:
set_default(var, val)
-- if variable "var" is not defined (not existed) then assign value
"val"